A known hose clamp will be described. Here, FIG. 17 is a perspective view showing a main part of a hose clamp that has been expanded. FIG. 18 is also a perspective view showing a main part of the hose clamp that has been constricted. FIG. 19 is a plan view showing a second operation piece.
As shown in FIG. 17, a hose clamp 910 has a clamp body 910A composed of a plate spring curved into a ring shape. A first operation piece 913 having a pair of legs 913a is formed on one end of the clamp body 910A. The first operation piece 913 has an operation portion 914 bent outwardly in a radial direction at ends of the legs 913a. In addition, a second operation piece 917 having a single leg 917a and protruding through a space between the legs 913a of the first operation piece 913 is formed on the other end of the clamp body 910A. The second operation piece 917 has an operation portion 938 bent outwardly in the radial direction at an end of the leg 917a and opposed to the operation portion 914 of the operation piece 913.
As shown in FIG. 18, an engaging claw 939 protruding outwardly in the radial direction is formed on the leg 917a of the second operation piece 917. In addition, the operation portion 914 of the first operation piece 913 has a receiving portion 930 and an opening 931. When the clamp body 910A is expanded, the receiving portion 930 can engage with the engaging claw 939, and while the clamp body 910A constricts, the opening 931 allows the engaging claw 939 to pass therethrough. Furthermore, an inclined slide guide portion 937 is formed on the leg 917a of the second operation piece 917. When the operation portions 914 and 938 come close to each other, the slide guide portion 937 slidably contacts with the leg 913a of the first operation piece 913 in order to make the engaging claw 939 be opposed to the opening 931.
Here, a hose clamp having the aforementioned construction is disclosed in, for example, Japanese Laid-Open Patent Publication No. 2003-090474.